Ammunition and a process for manufacturing the same

ABSTRACT

An ammunition such as a defensive grenade comprising an explosive body with preestablished fragmentation, a cartridge case and a fuse, said body acting as a support for the inner wall, the edge rotating band, the cartridge case and the fuse.

United States Patent [191 Theate Feb. 27, 1973 AMMUNITION AND A PROCESS FOR MANUFACTURING THE SAME [7 5] Inventor: Paul Theate, 4000 Liege, Belgium [73] Assignee: Fabrique Nationale dArmes de Gnerre, Societe Anonyme, Herstallez-Liege, Belgium 221 Filed: Nov. 20, 1969 21 Appl. No.: 878,396

[52] US. Cl ..102/67 [51] Int. Cl ..F42b 13/48 [58] Field of Search ..102/42, 67

[56] References Cited UNITED STATES PATENTS 1,367,464 2/1921 Cook ..lO2/38 1,154,437 9/1915 Rimailho ..l02/67 3,298,308 1/1967 Throner, Jr. ....102/67 2,972,949 2/1961 MacLeod 102/67 FOREIGN PATENTS OR APPLICATIONS 133,073 10/1919 Great Britain ..l02/67 524,903 5/1921 France Primary Examiner-Robert F. Stahl Attorney-Richards & Geier [57] ABSTRACT An ammunition such as a defensive grenade comprising an explosive body with preestablished fragmentation, a cartridge case and a fuse, said body acting as a support for the inner wall, the edge rotating band, the cartridge case and the fuse.

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A TTOILNEgS AMMUNITION AND A PROCESS FOR MANUFACTURING THE SAME This invention relates to an ammunition, more particularly to a defensive grenade and still more particularly to a grenade adopted to be thrown from a rifled bore tube.

This grenade is also of the type comprising an explosive body with a preestablished fragmentation generally made of a hollow body in plastic material functioning as a binder between fragments of hard bodies, generally steel shot or balls.

A first object of this invention is to provide such a defensive grenade so that the maximum amount of preestablished fragments or the maximum proportion of steel shot or balls are incorporated in a minimum space, said explosive body being otherwise conditioned for a maximum efficiency of the ammunition.

Another object of the invention is to manufacture such ammunition through a very simple mounting operation based on the application of the aforesaid explosive body as a binding support between all the essential parts of the ammunition.

Finally, another object of the invention concerns a simple process for manufacturing such ammunition.

These various requirements are satisfied in that the defensive grenade is made from a hollow explosive body in plastic material charged through its thickness with a maximum amount of fragments having a high hardness, said explosive body being conditioned to function as a support for an inner tightness cup, a rotating band covering its free edge, a cartridge case and a fuse.

In order to reach the maximum density and efficiency for the fragments of hard material, the hollow explosive body has a cylindrical-spherical shape.

The ammunition according to the invention has other different features which will be more apparent from the following detailed description of a non limitative example of an embodiment shown in the attached drawings in which:

FIG. 1 shows in an exploded view, partially in front view and partially in radial section, the characteristic elements of the ammunition according to the invention;

FIG. 2 shows on an enlarged scale and in radial section the explosive body provided with the tightness cup;

FIG. 3 is a plane view of FIG. 2; FIG. 4 is a partial section on the line IV-IV of FIG.

FIG. 5 is a view on the line V-V of FIG. 1;

FIGS. 6 and 7 show respectively a section on the lines Vl-VI and VII-VII of FIG. 5;

FIG. 8 shows in a front view with a partial radial section the ammunition according to the invention after having mounted the elements shown in the exploded view of FIG. 1;

FIG. 9 shows on a enlarged scale the portion indicated in F9 on FIG. 8.

In this embodiment, the essential elements of the ammunition comprise the explosive body 1, the cartridge case 2 and the fuse 3; the explosive body comprises substantially the explosive charge (not shown), the

' tightness cup 4, the composite body 5 securing the fragments of hard material 6 and the rotating band 7.

The explosive charge, the firing device and the fuse proper are neither described nor illustrated, being outside the scope of this invention it being possible to select these elements among the presently known means.

The explosive body 1 having a preestablished fragmentation has the form of a cylindrical spherical cup, i.e. it has a tubular portion 8 extended on one side by a hemispherical portion 9. The tubular portion 8 has two parallel ribs. 10-11 defining a peripheral groove 12 therebetween. The rib l1 outlines a shoulder 13 hearing the rotating band 7. Normally, the explosive body forms a unit with the tightness cup 4, the latter having also a tubular portion 14 and a hemispheric portion 15, said tubular portion having a thread 16 near its free edge. As shown more clearly in FIG. 2, the composite body 5 and the tightness cup 4 are firmly interlocked, the tightness cup forming the whole inner wall of the explosive body. Along its free edge, said explosive body has external notches of a half-circular shape. These notches 17 have the same depth and they are equally distributed on the periphery of the free edge of the explosive body 1.

Within the thickness of the explosive body is secured a maximum amount of steel balls 6 the diameter of which is slightly less than the thickness E of the thinnest portion of the explosive body 1. The rotating band 7 is applied with a tight fit upon the upper edge of the composite body. This rotating band has an annular shape the inner diameter D and the height H of which are substantially equal to the diameter D and the height H of the upper tubular portion of the composite body 5. The rotating band 7 has extra-thicknesses 18 directed inwardly and equally spaced on the periphery of the upper edge thereof, said extra-thicknesses having a value P' P with the same characteristics as those of notches 17 of the composite body as regards the number, the relative position, the shape and the sizes.

Near its lower edge, the rotating band 7 has one or several peripheral ribs 19 known per se and provided to cooperate with the riflings in the bore of the launching tube for rotating the ammunition about its longitudinal axis. The rotating band 7 is fitted on the upper portion of the composite body 5 so that, its lower edge contacting the shoulder 13, the extra-thicknesses 18 are completely engaging the respective notches 17 of the composite body. Thus, the so completed explosive body comprises the explosive charge, the inner tightness cup 4, the composite body 5 in which are secured the hard fragments and the rotating band 7 overtopping the explosive body. The ammunition is completed by the cartridge case 2 tightly fitted on the explosive body and the fuse 3 the threaded extension 21 of which is screwed on the threaded portion 16 of the tightness cup 4.

It will be observed that, in such original embodiment, the explosive body forms the binding element between the essential parts of the ammunition without any detrimental effect upon the mutual interlocking of a maximum amount of fragmented hard bodies within a minimum space.

The invention relates also to a process for the industrial manufacture of such ammunition. According to this process, by any suitable known means, the tightness cup 4 is firstly made from a thin sheet worked to form a hollow body the external shape and dimensions of which are strictly similar to those of the corresponding portions of the explosive body which the tightness cup must contact. This cup has namely a cylindrical-spherical shape, the free edge of the tubular cylindrical portion being profiled as a screwthread.

The so made cup is screwed on a metallic means (not shown) conforming precisely to the inner shape of the cup so as to prevent it from collapsing when injecting under pressure. The resulting core is then introduced into a mould the cavity of which has the shape and the sizes of the external portion of the explosive body. Between the mould and the core are introduced hard bodies, namely balls 6, and is injected under pressure the material likely to fill up correctly all the interstices between the balls and between the latter and the constituting walls of the mould, it being possible to use additional stresses such as vibrations, shakes, shocks or other similar means for placing the balls or the shot and to provide a complete filling. Of course, the binding material must be judiciously selected to satisfy various requirements such as the dimensional stability and the impact resistance at a normal temperature as well as when cold. Polyamides and superpolyamides as well as cellulose esters have been successfully experimented with.

Of course, it will be possible to choose the most suitable resins in accordance with the desired effects and the requirements being met, this being left to the decision of those skilled in the art, the characteristics of the synthetic resins being well known per se.

In the bottom of the mould these, have been provided small ribs to maintain the balls 6 at a slight distance a from the free edge of the composite body. When the latter has been stripped off, the rotating band 7 is applied thereto with a tight fit and the surfaces outlined by the upper annular edge 21 and the inner extrathicknesses 18 are straightened out by mechanization so that they are outlined by the plane X-X.

The aforesaid distance 6 has been provided by inserting suitable small ribs 22 in the mould for keeping systematically the balls 6 outside the surfacing tool.

The cartridge case 2 and the fuse 3 may be known elements made by known processes and means. Said fuse will advantageously include a centering bearing 23 cooperating with a corresponding annular stop 23 formed on the upper free edge of the composite material so that both elements, namely the explosive body 1 and the fuse 3, are perfectly concentric to each other when screwed.

As previously disclosed, for completing the ammunition, it is sufficient to secure the rotating band on the explosive body forming a unit with the tightness cup, to proceed with filling up, to fasten the cartridge case 2 and finally to secure fuse 3.

It is of course apparent that the charges, the priming cups and the fuses will be judiciously selected among the various known means.

The invention relates to the ammunition as such and more particularly to the characteristic explosive body as well as to the process described for realizing the one and the other.

The characteristics disclosed herein may be also carried out for making ammunition not only having different sizes, but also likely to present numerous variations provided that the essential and characteristic elements are maintained.

What I claim is: 1. Ammunition, such as a defensive grenade, comprising in combination, a hollow composite supporting body having a spherical wall portion and a cylindrical wall portion integral with said spherical portion and having an open end, fragments of hard material embedded within the walls of said body, an inner wall constituting a lining for said body, a driving ring tightly fitting around said cylindrical portion adjacent said open end, a fuse head having a part connected to said inner wall and another part abutting against said ring, and a protective casing tightly fitting around said supporting body and abutting against said ring.

2. An ammunition according to claim 1, wherein said composite body is made of a synthetic resin securing the fragmented hard bodies, generally steel balls, within the thickness thereof.

3. An ammunition according to claim 2, characterized in that the inner tightness wall is under the form of a thin metallic cup having a cylindrical-spherical shape the free edge of the cylindrical portion of which is profiled to form a screw thread, the composite body proper made of the synthetic resin securing the fragments of the hollow bodies being mouled upon the said tightness cup.

4. An ammunition according to claim 3, characterized in that the cylindrical portion of the composite body has an outer shoulder and peripheral notches correlative with the shape and the sizes of the rotating band interlocked with said composite body through a tight fit.

5. An ammunition according to claim 3 characterized in that the fragments of the hollow bodies or the steel balls are kept at a slight distance from the peripheral free edge of said composite body when making the latter.

6. An ammunition according to claim 3, characterized in that the rotating band comprises substantially an annular element having, inwardly and along its upper peripheral edge, extra-thicknesses the number, the sizes and the relative position of which are conditioned in accordance with the notches of the peripheral free edge of the composite body proper.

7. An ammunition according to claim 3, characterized in that, the composite body forming a unit with the inner tightness cup and the rotating band, the cartridge case is fastened by a pressure fit upon the cylindrical portion of the composite body proper, whereas the fuse is secured by screwing its threaded extension upon a screw thread formed on the said tightness cup.

8. An ammunition according to claim 7, characterized in that the fuse has a centering bearing cooperating with an annular stop of the composite body so that the latter and the fuse are concentric to each other when screwed. 

2. An ammunition according to claim 1, wherein said composite body is made of a synthetic resin securing the fragmented hard bodies, generally steel balls, within the thickness thereof.
 3. An ammunition according to claim 2, characterized in that the inner tightness wall is under the form of a thin metallic cup having a cylindrical-spherical shape the free edge of the cylindrical portion of which is profiled to form a screw thread, the composite body proper made of the synthetic resin securing the fragments of the hollow bodies being mouled upon the said tightness cup.
 4. An ammunition according to claim 3, characterized in that the cylindrical portion of the composite body has an outer shoulder and peripheral notches correlative with the shape and the sizes of the rotating band interlocked with said composite body through a tight fit.
 5. An ammunition according to claim 3 characterized in that the fragments of the hollow bodies or the steel balls are kept at a slight distance from the peripheral free edge of said composite body when making the latter.
 6. An ammunition according to claim 3, characterized in that the rotating band comprises substantially an annular element having, inwardly and along its upper peripheral edge, extra-thicknesses the number, the sizes and the relative position of which are conditioned in accordance with the notches of the peripheral free edge of the composite body proper.
 7. An ammunition according to claim 3, characterized in that, the composite body forming a unit with the inner tightness cup and the rotating band, the cartridge case is fastened by a pressure fit upon the cylindrical portion of the composite body proper, whereas the fuse is secured by screwing its threaded extension upon a screw thread formed on the said tightness cup.
 8. An ammunition according to claim 7, characterized in that the fuse has a centering bearing cooperating with an annular stop of the composite body so that the latter and the fuse are concentric to each other when screwed. 